The resolution of a microscope depends critically on the size of the aperture of its objective lens. Achieving a wide aperture, and thereby high resolution, requires that the lens be large and close to the specimen, and further it is necessary to fill the space between the specimen and the lens with a material whose refractive index matches that of the lens to prevent light loss at steep angles from reflection (oil immersion). We are attempting to apply the concept of scanned aperture radar (SAR) to eliminate both the need for a lens close to the specimen and for oil immersion of the specimen. If successful, the result will be a general-purpose, lensless microscope with a resolving power double the theoretical limit for a microscope with a lens and with an arbitrarily long working distance. The microscope operates by collecting the phase and amplitude of scattered light from the specimen sequentially, hence "scanned aperture" and the image is reconstructed from selected Fourier components after all the data have been collected using a high-speed optical processor developed by the Essex Corporation for SAR work.